Concert promoters on Wednesday more than doubled Jackson's summer run of concerts in London after advance tickets sold out within hours of going on sale.
AEG Live said an advance allotment of half the tickets for the 10 shows in July sold out soon after going on sale. Eighteen concerts have been added into September, and more shows are possible.
Ticket-seller Ticketmaster apologized for problems experienced by fans after its computer system crashed. Managing director Chris Edmonds said the glitches were the result of "an unprecedented level of demand."
Fifty to seventy-five pounds (US$70 to 105) tickets and special "Thriller Hospitality Packages" worth 795 pounds (US$1,104) were on sale to buyers who registered online. Half the tickets for each show have been held back and go on sale to the general public Friday morning.
The 50-year-old King of Pop has said the shows at the 20,000-capacity O2 Arena in south London will be his last in the British capital.
Jackson has sold more than 750 million albums and won 13 Grammys, but has not staged a major tour since 1997 or released an album of new material since 2001 "Invincible" album.
Jackson has appeared in public infrequently since being acquitted of child molestation in California in 2005, and he has struggled to pay his debts.
The London shows are entitled "This is It," and Jackson said they would be his swan song — although AEG said the gigs could be part of a bigger, final world tour.
Britain's Sun newspaper quoted AEG boss Randy Phillips as saying Jackson would release a new single before the first of his London concerts.
But it remains to be seen whether Jackson is up to a lengthy tour. His last live performance in Britain was at the 2006 World Music Awards, when he managed just a few lines of "We Are the World" before leaving the stage.
A video of Jackson trying to record a new single, shown at a British court last year when Jackson was being sued for breach of contract, showed him struggling to keep up his powerful vocals.
(Agencies March 12, 2009)
